In current methods of sealing a structure against liquid leaks, for example an aircraft fuel tank, ensuring liquid will not leak from the structure is a very time consuming process. A sealant must be applied over all of the joints of the structure and over all of the fasteners of the structure. This application of sealant can take considerable time.
Additionally, inspecting the sealant applied to the joints of the structure and the fasteners of the structure is also very time consuming.
In current methods of sealing joints between two parts of a structure and/or sealing a fastener in a part of a structure, a technician applies the sealant by hand. The sealant is typically in a low/sag thixotropic paste form. In a structure such as an aircraft fuel tank, the technician will apply the sealant around hundreds and potentially thousands of fasteners in the fuel tank structure by a paint brush. Additionally, applying sealant to fasteners in the structure often requires the technician to manipulate the brush in some very confined spaces. Along joints of the structure, the sealant is applied by a sealant gun similar to a caulk gun that is used to apply caulk in residential applications. The technician applies the sealant using the sealant gun and then forms the applied sealant to the joints by hand using a tool that resembles a spatula.
The technician applying sealant around the structure fasteners using a paint brush and applying sealant along the joints of the structure using the spatula are both time consuming processes. The technicians who apply sealant in aircraft applications, for example an aircraft fuel tank are typically required to work 12 hour days, seven days a week. Given the manual and repetitive nature of applying the sealant, the application of the sealant can lead to repetitive stress injuries to the technician.
Inspection of the sealant applied to the structure requires an inspector to come to the work site and inspect every sealed fastener and every inch of sealed joint on the structure. This inspection process is also time consuming, both in waiting for the inspector to be available at the work site, and for the inspector to inspect every sealed fastener and every inch of sealed joint. While the inspection is conducted, the technician waits for the inspection to be complete. Furthermore, the inspection process is prone to human error and human subjectivity.